Notion of Absolute Clock Synchronization in SR
in [Relativity]
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From: Tom Adams on 8 Apr 2010 08:29 On Apr 7, 10:05 pm, "Androcles" <Headmas...(a)Hogwarts.physics_x> wrote: > "Tom Adams" <tadams...(a)yahoo.com> wrote in message > > news:3cfbbdd8-1c7e-4113-9ea9-d9ee6a4cf187(a)g30g2000yqc.googlegroups.com... > On Apr 7, 3:21 am, "Androcles" <Headmas...(a)Hogwarts.physics_x> wrote: > > > > > > > "Tom Adams" <tadams...(a)yahoo.com> wrote in message > > >news:827aa470-d686-4b02-a943-ada1caebe193(a)g30g2000yqc.googlegroups.com.... > > On Mar 11, 11:35 am, GSS <gurcharn_san...(a)yahoo.com> wrote: > > > > As per Newtonian notion of absolute space and time, clocks can be > > > synchronized in absolute terms such that identical precision atomic > > > clocks located anywhere within the solar system and in any state of > > > motion, will read the same time t1 when a standard master clock reads > > > t1. This notion of absolute clock synchronization implies the notion > > > of absolute simultaneity. > > > > However, as per SR, spatial distance and time measurements have been > > > rendered 'relative' and cannot be the same value for different > > > observers in different states of motion. As per SR the notion of > > > global 'absolute simultaneity' is fundamentally invalid for different > > > observers in different states of motion. Therefore, the notion of > > > global 'absolute clock synchronization' (in contrast to e- > > > synchronization) is no longer valid in SR. > > > > Since the term 'absolute clock synchronization' is often used in > > > discussions, I would like to request some Relativity experts to kindly > > > clarify the precise definition of absolute clock synchronization in > > > SR. Kindly illustrate the procedure, through some 'thought experiment' > > > or 'gedanken', to achieve absolute clock synchronization for all > > > observers in different states of motion within our solar system. > > > > Further, I also need some expert opinion on the following situation, > > > involving clock synchronization. > > > > Two identical precision atomic clocks are positioned side by side at > > > point A on the surface of earth and mutually synchronized to ensure > > > that > > > (a) their clock rates or frequencies are exactly matched or > > > synchronized > > > (b) their instantaneous timing offsets are eliminated to ensure that a > > > common trigger pulse yields the same timing reading t1 from both > > > clocks. > > > > Assuming the inherent drift of the two atomic clocks is identical and > > > well within 100 ps per day, it can be demonstrated that while the two > > > clocks remain side by side, their synchronization, after a period of > > > one day, is retained at well within one ns accuracy. > > > > Let us shift one of the synchronized atomic clocks to a position B > > > such that distance AB is about 30 km. > > > Stop right there. You are outside of the scope of SR. All acceleration > > is outside the scope. SR cannot address your question. > > > Strictly speaking, the twin paradox is not part of SR since in > > involves acceleration. The space-time paths that the twins take do > > involve different elapsed times in a reference frame, but taking one > > of the paths involves acceleration. > > =========================================== > > Stop right there. > > Strictly speaking, the twin paradox is very much part of SR since it does > > NOT involve acceleration. > > The outbound journey is at velocity v and the inbound is at velocity -v, > > the > > path is a two-sided polygon. > > Yes, but the twin has to go from v to -v. > ====================================== > Not relevant, v is squared in tau = t * sqrt(1-v^2/c^2), > so (-v)^2 = v^2. Cars go around oval race tracks without > changing speed all the time, reversing their velocity. > ====================================== > > > > > "If we assume that the result proved for a polygonal line is also valid > > for > > a continuously curved line, we arrive at this result: If one of two > > synchronous clocks at A is moved in a closed curve with constant velocity > > until it returns to A, the journey lasting t seconds, then by the clock > > which has remained at rest the travelled clock on its arrival at A will be > > 1/2 t v^2/c^2 second slow." -- Einstein, 1905, "On the Electrodynamics of > > Moving Bodies". > > Yeah, it's in the paper. But there is acceleration. > ======================================= > If there were then its duration and distance would be pertinent. > Unless you can state their relevance then acceleration is just so > much hand-waving, like Gordon Brown dog-paddling the economy > as he sinks, flapping his paws up and down and saying "No", > and "Should" without answering any questions. > > Einstein claims his result is proved for a polygonal line and a > continuous curved line, there is no change in SPEED (not velocity) > as the ship swings around the back of the star and returns to Earth. > He contradicts his own xi = x'/sqrt(1-v^2/c^2), eta = y, zeta = z, > but that's normal for his nonsense. > ======================================= > > > Thence we conclude that clock B (having travelled and being younger than > > clock A) meets clock A before clock A meets clock B. The clock are twin > > clocks, and in real physics A meets B when B meets A. That's the paradox. > > No, there is no real paradox. > ==================================================== > Oh yes there is, > http://www.merriam-webster.com/dictionary/paradox > > 2 a : a statement that is seemingly contradictory or opposed to common sense > and yet is perhaps true > b : a self-contradictory statement that at first seems true > c : an argument that apparently derives self-contradictory conclusions by > valid deduction from acceptable premises > > As the ship goes around turns 2 and 3 it travels at v = 0 when u = > <unchanged speed>, > so > eta = y'/sqrt(1-u^2/c^2) > and NOT > eta = y > Einstein wasn't bright enough to know the difference between speed > and velocity, he was too busy reading sci-fi in school. > ==================================================== > > One twin accelerated and the other did not. You can't just reverse A > and B. > =================================================== > > Einstein can! He can do as he likes, He's a god. He can defy the laws of > physics. He's holy, a genius. The important thing is that *you* can't reverse A and B because they took different paths in space-time. No inertial frame will consider these two paths to be equivalent. Einstein did not reverse them either. > =================================================== > You can demonstrate the so-called "paradox" within SR by having the > clock traveling at v pass close to another clock traveling back at - > v. When they are close together they can synchronize. But when the > clock traveling at -v gets back to the clock at rest, it will now be > "younger" (less time ticked off) demonstrating that one path through > space-time gets to the future faster than the other. > ==================================================== > That's what I said, B meets A before A meets B. It's a whole lot > harder to do than mere instant acceleration in zero time. > > > > > > >http://www.merriam-webster.com/dictionary/paradox > > > 2 a : a statement that is seemingly contradictory or opposed to common > > sense > > and yet is perhaps true > > > b : a self-contradictory statement that at first seems true > > > c : an argument that apparently derives self-contradictory conclusions by > > valid deduction from acceptable premises > > > No need for any word salad about 'synchronized' or 'spacetime' or > > 'acceleration', the paradox is: B meets A before A meets B, contradictory > > to > > the acceptable premise that A meets B when B meets A. > > > ================================================- Hide quoted text - > > - Show quoted text -- Hide quoted text - > > - Show quoted text -
From: GSS on 8 Apr 2010 09:43 On Apr 7, 1:15 am, Tom Roberts <tjroberts...(a)sbcglobal.net> wrote: > GSS wrote: >> On Apr 6, 8:13 am, Tom Roberts <tjroberts...(a)sbcglobal.net> wrote: >>> GSS wrote: >>>> On Apr 3, 9:12 pm, Tom Roberts <tjroberts...(a)sbcglobal.net> wrote: >>>>> By saying "inertial frame" you imply the context is SR -- in SR one could set >>>>> the offsets of two clocks such that they are synchronized in any inertial frame >>>>> you choose. They would be synchronized with each other in that frame, but not >>>>> with coordinate clocks of the selected frame (these two would "tick at a >>>>> different rate" than those coordinate clocks). >>>> You have made a very important statement which I would like to repeat >>>> with some emphasis. "In SR one could set the *offsets* of two clocks >>>> such that they are *synchronized* in *any* inertial frame you choose. >>>> They would be synchronized with each other in *that* frame." >>>> Let us extend the analogy of two clocks fixed on earth's geoid to a >>>> million (or more) clocks fixed on earth's geoid. Let us synchronize >>>> all these clocks in ECI frame by synchronizing their time to UTC by >>>> using GPS service. In this state, each and every adjoining pair of >>>> clocks can be considered as mutually synchronized with zero time >>>> offset between them. .... >>> But, of course, each pair is synchronized in the ECI frame. The concept >>> "synchronized" is ALWAYS qualified with a frame. > >>>> Let us *adjust* the offsets of all these clocks such that they are now >>>> synchronized in BCRF. >>> It is not possible to make such an "adjustment". They all have essentially the >>> same gravitational potential, but they have different speeds relative to the >>> BCRF -- the earth both rotates and revolves around the sun. > >> As per your statement above, "They would be synchronized with each >> other in that [BCRF] frame, but not with coordinate clocks of the >> selected [BCRF] frame (these two would "tick at a different rate" than >> those coordinate clocks)." > > That was for two clocks AT REST IN SOME INERTIAL FRAME, being synchronized in > some other inertial frame. No. I had pointed out to you earlier too that the two clocks under consideration in this thread (clocks A and B fixed on earth's geoid and separated by distance S), CAN NEVER BE AT REST IN ANY INERTIAL FRAME. Your statement above reads, "But, of course, each pair is synchronized in the ECI frame. The concept "synchronized" is ALWAYS qualified with a frame." There is no mention of *at rest* in your statement. > Here the clocks on the geoid are NOT at rest in ANY > inertial frame, and my "statement above" does not apply. > > Remember that the context in which statements are made is important, and you > cannot take a statement from one context, apply it in a different context, and > expect it to remain valid. > Wrong, I have not changed the context. Throughout this thread I have consistently used the context of 'two identical precision atomic clocks A and B, fixed on the surface of earth (implying geoid) and separated by finite distance S (or D) of the order of 30 km. The only reference frames considered in these discussions are, (a) The local or Lab frame of the clocks, fixed on the surface of earth, in which the clocks under consideration are at rest. But you have refused to consider it an 'inertial reference frame' for the purpose of clock synchronization. You have repeatedly emphasized that as per SR, the term 'synchronization of clocks' is only valid when the synchronization is done in *some inertial reference frame*. (b) The ECI reference frame, which you have accepted as an 'inertial' reference frame in SR. In this reference frame your stand has often been contradictory. In one post you accept that the pair of clocks under consideration when synchronized to UTC time through GPS, can be regarded as mutually synchronized in the ECI inertial frame. In the next post you assert that a pair of clocks under consideration can be synchronized in *any inertial reference frame* only when the two clocks are *at rest* in that (or *some inertial*) reference frame. Here there is a vagueness in your stand. It is not clear whether by referring to the *AT REST IN SOME INERTIAL FRAME* requirement, you are accepting the local or lab frame (a) of the clocks, as the *inertial reference frame*, or whether you are denying the mutual synchronization of the two clocks under consideration, in the ECI frame. (c) The BCRF inertial reference frame. At one stage you declared that if the two clocks under consideration are mutually synchronized in one (say ECI) inertial reference frame, they can be mutually synchronized in another (say BCRF) inertial reference frame simply by *setting* the offsets of the clocks accordingly. Later on you retracted your position and stated that the clock pair under consideration cannot be mutually synchronized in BCRF because of their changing speed in that frame. On second thoughts you declared, "in SR one could set the offsets of two clocks (under consideration) such that they are synchronized in *BCRF* inertial frame (you choose). They would be synchronized with each other in that (BCRF) frame, but not with coordinate clocks of the selected (BCRF) frame (these two would "tick at a different rate" than those coordinate clocks)." However, in the latest post you have again changed your stand and now demand that the two clocks under consideration must be AT REST IN SOME INERTIAL FRAME to enable their mutual synchronization in BCRF. (d) The Galactic reference frame. Of course, the discussions were invariably scuttled before reaching this frame. Finally, let me sum up your SR dominated viewpoint which I am unable to agree with. (i) When two clocks under consideration are mutually synchronized, they represent a physical phenomenon which must not change with our arbitrary choice of a reference frame. But you refuse to accept it as a physical phenomenon, essentially to protect the validity of second postulate of SR. (ii) When two clocks under consideration are mutually synchronized on earth's geoid, you refuse to call them 'synchronized' because in your opinion the term 'synchronization' has been reserved for use in conjunction with 'inertial reference frames' and the earth's geoid does not represent an inertial reference frame. (iii) You believe that the two clocks under consideration can be mutually synchronized in any inertial reference frame only if the pair of clocks are AT REST IN SOME INERTIAL FRAME. Since the pair of clocks under consideration cannot practically be at rest in any *inertial reference frame*, it obviously implies that the given pair of atomic clocks cannot be physically synchronized in any inertial reference frame whatsoever. This awkward position or belief too is ultimately aimed at protecting the validity of the second postulate of SR. Well, if you don't consider it necessary to clarify your position, let us agree to close these discussions here. GSS
From: Tom Adams on 8 Apr 2010 10:21 On Apr 7, 3:32 am, "Androcles" <Headmas...(a)Hogwarts.physics_x> wrote: > "Tom Adams" <tadams...(a)yahoo.com> wrote in message > > news:d48f740f-4aa9-4fc2-ad2f-41a59f23816f(a)w42g2000yqm.googlegroups.com... > On Mar 12, 9:31 am, GSS <gurcharn_san...(a)yahoo.com> wrote: > > > > > > > On Mar 11, 10:58 pm, PD <thedraperfam...(a)gmail.com> wrote: > > > > On Mar 11, 9:35 am, GSS <gurcharn_san...(a)yahoo.com> wrote: > > > >> As per Newtonian notion of absolute space and time, clocks can be > > >> synchronized in absolute terms such that identical precision atomic > > >> clocks located anywhere within the solar system and in any state of > > >> motion, will read the same time t1 when a standard master clock reads > > >> t1. This notion of absolute clock synchronization implies the notion > > >> of absolute simultaneity. > > > >> However, as per SR, spatial distance and time measurements have been > > >> rendered 'relative' and cannot be the same value for different > > >> observers in different states of motion. As per SR the notion of > > >> global 'absolute simultaneity' is fundamentally invalid for different > > >> observers in different states of motion. Therefore, the notion of > > >> global 'absolute clock synchronization' (in contrast to e- > > >> synchronization) is no longer valid in SR. > > > >> Since the term 'absolute clock synchronization' is often used in > > >> discussions, I would like to request some Relativity experts to kindly > > >> clarify the precise definition of absolute clock synchronization in > > >> SR. > > > > Sure. One such procedure is as follows. > > > 1. Start at clock A and note the time T1. > > > 2. Proceed to clock B by any method of travel that is guaranteed to be > > > at constant speed. > > > 3. At arrival at clock B, note the time T2. > > > 4. Proceed back to clock A by the same method of travel, and at the > > > same speed. > > > 5. At arrival at clock A, note the time T3. > > > 6. If T3-T2 = T2 - T1, then the clocks are synchronized. If T3-T2 > T2- > > > T1, then clock B is running slow and should be set forward by half the > > > difference noted. If T3-T2 < T2-T1, then clock B is running fast and > > > should be set back by half the difference noted. > > > >> Kindly illustrate the procedure, through some 'thought experiment' > > >> or 'gedanken', to achieve absolute clock synchronization for all > > >> observers in different states of motion within our solar system. > > > > This cannot be done, given what we know about the laws of physics. > > > >> Further, I also need some expert opinion on the following situation, > > >> involving clock synchronization. > > > >> Two identical precision atomic clocks are positioned side by side at > > >> point A on the surface of earth and mutually synchronized to ensure > > >> that > > >> (a) their clock rates or frequencies are exactly matched or > > >> synchronized > > >> (b) their instantaneous timing offsets are eliminated to ensure that a > > >> common trigger pulse yields the same timing reading t1 from both > > >> clocks. > > > >> Assuming the inherent drift of the two atomic clocks is identical and > > >> well within 100 ps per day, it can be demonstrated that while the two > > >> clocks remain side by side, their synchronization, after a period of > > >> one day, is retained at well within one ns accuracy. > > > >> Let us shift one of the synchronized atomic clocks to a position B > > >> such that distance AB is about 30 km. As per Newtonian notion of > > >> absolute space and time, the mutual synchronization of the two clocks, > > >> positioned at points A and B, will be retained in tact and this > > >> synchronization can be referred as 'absolute synchronization'. But > > >> according to SR, the mutual synchronization of the two clocks will > > >> 'breakdown' during the shifting of one of the clocks from point A to > > >> point B. > > > > No, this is not what SR says. The clocks are still synchronized in the > > > frame in which they are at rest. However, they are not synchronized in > > > any frame where the two clocks are moving. > > > You say that two clocks 'synchronized' in their rest frame, are 'not > > synchronized' in any other frame where the clocks are moving. Let us > > examine the plausibility of this statement. When two identical > > precision atomic clocks are said to be 'synchronized' in their rest > > frame, essentially their clock frequencies are supposed to have been > > perfectly matched. > > The matching of the two frequencies is a physical > > phenomenon, controlled through their hardware circuitry and > > sophisticated components. > > In SR, physical phenomena are defined in 4D space-time. They are > all systems of events. They have no fixed defintion for all reference > frames. > > > But when the same two clocks are 'viewed' by > > different observers in different states of motion, they appear to be > > out of synchronization. That is their clock frequencies 'appear' to be > > mismatched by different amount to different observers in different > > states of motion. > > > However, creating a mismatch in the clock frequencies of two clocks is > > a physical phenomenon controlled through their hardware circuitry and > > sophisticated components. How do you think different observers in > > different states of motion actually manage to physically influence the > > hardware circuitry and sophisticated components of the two clocks to > > create different amounts of mismatch in their frequencies, through the > > mere act of 'viewing' from a distance? Do you think there is some > > 'magic' involved in creating this phenomenon, which ordinary humans > > cannot understand? > > The observers don't influence the system of events I referred to > earlier. Each reference frame uses the operational definition of > simultaneity and comes up with a different subset of events that thay > consider to be simultaneous. So they disagree on whether the clocks > are synchronous. > > Physical objects are systems of events in space-time. The objects > viewed from a reference frame are projections into space and time, > they are like shadows that change based on the angle of projection. > > > > > GSS- Hide quoted text - > > > - Show quoted text - > > You are a physical object that does not change as the angle of the sun > changes. So how can your shadow be so different with different > angles. That's what you are asking, you seem to think that is a > paradox. > > ============================================ > A sundial is a physical object and is a clock. A twin sundial goes > on an accelerated relativistic journey and returns beside the sundial > that remained at rest. The sundial that travelled is now younger than > the sundial that remained. > So how can its shadow be so different with different angles? > That's what I am asking, I seem to think that is a paradox. > -- Androcles.- Hide quoted text - > > - Show quoted text - One of the sundials just took a space-time path to the future that took less time. It's a paradox in the sense that it seems impossible from our everyday way of thinking, but it's not a contradiction. The seeds of this possiblilty was already in our everyday idioms. You can meet and old friend and say "It's seems like only yesterday when we were last together" and it won't raise a eyebrow. But try saying "It seems like only tomorrow..."
From: Tom Adams on 8 Apr 2010 10:29 On Apr 7, 4:42 pm, Tom Roberts <tjroberts...(a)sbcglobal.net> wrote: > Tom Adams wrote: > > Stop right there. You are outside of the scope of SR. All acceleration > > is outside the scope. SR cannot address your question. > > This is just plain not true. SR can handle acceleration just fine. Of course an > accelerated system is not an inertial frame, but the math is self-consistent, > meaningful, and agrees with experiments. It is also complicated, so one must be > careful. > > SR is used to model particle ACCELERATORS all the time. > > SR cannot handle gravitation -- in relativity that is modeled as a curved > manifold, and the equations of SR require that the manifold be flat. Indeed, GR > can be considered to be SR generalized to non-flat manifolds; the increase in > complexity is enormous, and the change in ontology is significant.... > > > Strictly speaking, the twin paradox is not part of SR since in > > involves acceleration. > > This is also not true, for the same reason. > > Tom Roberts You are probably right. Just a matter of calculus. There are SR effects and separate acceleration effects on the clocks. I learned something for once on this group. Anyway, it's possible to show the "paradox" without acceleration. You just have 2 clocks in 2 inertial frames pass each other close together and you synchronize them when they are close. You can get sufficient sychronization that way between a clock moving away from our clock and the clock returning to our clock. In the idealized version, the two clocks participate in the same event (somehow without colliding) and are perfectly synchronized.
From: Androcles on 8 Apr 2010 11:37
"Tom Adams" <tadamsmar(a)yahoo.com> wrote in message news:bd7d58e3-eac1-4128-aeb5-d4c4cefdc10f(a)z3g2000yqz.googlegroups.com... On Apr 7, 3:32 am, "Androcles" <Headmas...(a)Hogwarts.physics_x> wrote: > "Tom Adams" <tadams...(a)yahoo.com> wrote in message > > news:d48f740f-4aa9-4fc2-ad2f-41a59f23816f(a)w42g2000yqm.googlegroups.com... > On Mar 12, 9:31 am, GSS <gurcharn_san...(a)yahoo.com> wrote: > > > > > > > On Mar 11, 10:58 pm, PD <thedraperfam...(a)gmail.com> wrote: > > > > On Mar 11, 9:35 am, GSS <gurcharn_san...(a)yahoo.com> wrote: > > > >> As per Newtonian notion of absolute space and time, clocks can be > > >> synchronized in absolute terms such that identical precision atomic > > >> clocks located anywhere within the solar system and in any state of > > >> motion, will read the same time t1 when a standard master clock reads > > >> t1. This notion of absolute clock synchronization implies the notion > > >> of absolute simultaneity. > > > >> However, as per SR, spatial distance and time measurements have been > > >> rendered 'relative' and cannot be the same value for different > > >> observers in different states of motion. As per SR the notion of > > >> global 'absolute simultaneity' is fundamentally invalid for different > > >> observers in different states of motion. Therefore, the notion of > > >> global 'absolute clock synchronization' (in contrast to e- > > >> synchronization) is no longer valid in SR. > > > >> Since the term 'absolute clock synchronization' is often used in > > >> discussions, I would like to request some Relativity experts to > > >> kindly > > >> clarify the precise definition of absolute clock synchronization in > > >> SR. > > > > Sure. One such procedure is as follows. > > > 1. Start at clock A and note the time T1. > > > 2. Proceed to clock B by any method of travel that is guaranteed to be > > > at constant speed. > > > 3. At arrival at clock B, note the time T2. > > > 4. Proceed back to clock A by the same method of travel, and at the > > > same speed. > > > 5. At arrival at clock A, note the time T3. > > > 6. If T3-T2 = T2 - T1, then the clocks are synchronized. If T3-T2 > > > > T2- > > > T1, then clock B is running slow and should be set forward by half the > > > difference noted. If T3-T2 < T2-T1, then clock B is running fast and > > > should be set back by half the difference noted. > > > >> Kindly illustrate the procedure, through some 'thought experiment' > > >> or 'gedanken', to achieve absolute clock synchronization for all > > >> observers in different states of motion within our solar system. > > > > This cannot be done, given what we know about the laws of physics. > > > >> Further, I also need some expert opinion on the following situation, > > >> involving clock synchronization. > > > >> Two identical precision atomic clocks are positioned side by side at > > >> point A on the surface of earth and mutually synchronized to ensure > > >> that > > >> (a) their clock rates or frequencies are exactly matched or > > >> synchronized > > >> (b) their instantaneous timing offsets are eliminated to ensure that > > >> a > > >> common trigger pulse yields the same timing reading t1 from both > > >> clocks. > > > >> Assuming the inherent drift of the two atomic clocks is identical and > > >> well within 100 ps per day, it can be demonstrated that while the two > > >> clocks remain side by side, their synchronization, after a period of > > >> one day, is retained at well within one ns accuracy. > > > >> Let us shift one of the synchronized atomic clocks to a position B > > >> such that distance AB is about 30 km. As per Newtonian notion of > > >> absolute space and time, the mutual synchronization of the two > > >> clocks, > > >> positioned at points A and B, will be retained in tact and this > > >> synchronization can be referred as 'absolute synchronization'. But > > >> according to SR, the mutual synchronization of the two clocks will > > >> 'breakdown' during the shifting of one of the clocks from point A to > > >> point B. > > > > No, this is not what SR says. The clocks are still synchronized in the > > > frame in which they are at rest. However, they are not synchronized in > > > any frame where the two clocks are moving. > > > You say that two clocks 'synchronized' in their rest frame, are 'not > > synchronized' in any other frame where the clocks are moving. Let us > > examine the plausibility of this statement. When two identical > > precision atomic clocks are said to be 'synchronized' in their rest > > frame, essentially their clock frequencies are supposed to have been > > perfectly matched. > > The matching of the two frequencies is a physical > > phenomenon, controlled through their hardware circuitry and > > sophisticated components. > > In SR, physical phenomena are defined in 4D space-time. They are > all systems of events. They have no fixed defintion for all reference > frames. > > > But when the same two clocks are 'viewed' by > > different observers in different states of motion, they appear to be > > out of synchronization. That is their clock frequencies 'appear' to be > > mismatched by different amount to different observers in different > > states of motion. > > > However, creating a mismatch in the clock frequencies of two clocks is > > a physical phenomenon controlled through their hardware circuitry and > > sophisticated components. How do you think different observers in > > different states of motion actually manage to physically influence the > > hardware circuitry and sophisticated components of the two clocks to > > create different amounts of mismatch in their frequencies, through the > > mere act of 'viewing' from a distance? Do you think there is some > > 'magic' involved in creating this phenomenon, which ordinary humans > > cannot understand? > > The observers don't influence the system of events I referred to > earlier. Each reference frame uses the operational definition of > simultaneity and comes up with a different subset of events that thay > consider to be simultaneous. So they disagree on whether the clocks > are synchronous. > > Physical objects are systems of events in space-time. The objects > viewed from a reference frame are projections into space and time, > they are like shadows that change based on the angle of projection. > > > > > GSS- Hide quoted text - > > > - Show quoted text - > > You are a physical object that does not change as the angle of the sun > changes. So how can your shadow be so different with different > angles. That's what you are asking, you seem to think that is a > paradox. > > ============================================ > A sundial is a physical object and is a clock. A twin sundial goes > on an accelerated relativistic journey and returns beside the sundial > that remained at rest. The sundial that travelled is now younger than > the sundial that remained. > So how can its shadow be so different with different angles? > That's what I am asking, I seem to think that is a paradox. > -- Androcles.- Hide quoted text - > > - Show quoted text - One of the sundials just took a space-time path to the future that took less time. ============================================ That's handwaving. If it took less time it should record less time. Prove your case. It's a paradox in the sense that it seems impossible from our everyday way of thinking, but it's not a contradiction. ========================================== More handwaving. How can its shadow angle be different from the shadow angle of the sundial that is beside it? Let's talk about a balance clock as the bozo Einstein does. The hands count oscillations of the balance wheel, they are merely a divider gear train. A digital watch counts oscillations of a quartz crystal electronically. If they record more or less time then the count of the oscillations is greater or less. Prove that the count changes because the clock moves. The seeds of this possiblilty was already in our everyday idioms. ========================================== We are not discussing vague possibilities, Einstein ASSERTS that the count of the balance wheel's oscillations is different, some counts have been lost because the clock moved. Einstein ASSERTS that time itself changes, but a sundial doesn't show it. Produce an experiment that supports Einstein's ridiculous claim. You can meet and old friend and say "It's seems like only yesterday when we were last together" and it won't raise a eyebrow. But try saying "It seems like only tomorrow..." ========================================== Doesn't matter how subjectively you record time, a clock is an objective instrument and when I wake up I look at the clock, not listen to my own impressions of what time it is. The clock is always in agreement with the sun, I know when to expect sunrise and sunset. Quite handwaving and PROVE the clock lost some oscillations because it moved. In particular, show an atomic clock lost some oscillations because it moved, i.e. the moving clock has less than 9 192 631 770 "ticks" per second of the stationary clock. Ref: http://physics.nist.gov/cuu/Units/second.html |